Drug-eluting stents: a pharmacoclinical perspective.

In the 26 years since Gruntzig introduced a simple balloon angioplasty technique, percutaneous coronary intervention has made extraordinary progress and has now surpassed bypass surgery in frequency. The area of coronary stenting has been the focus of intense research. One of the major problems encountered after stenting is an exaggerated vascular neointimal proliferation called in-stent stenosis. The evolution of drug-eluting stents has helped in reducing the incidence of in-stent stenosis by almost half. A number of pharmacological agents have been tried in coronary stents with varying degrees of success; many more are being developed and tested. Serious doubts have been expressed about the pharmacoeconomics of drug-eluting stents compared with bare metal stents, because of the huge disparity in costs. Drug-eluting stents, which can be grouped under both device and instrument, have thrown up interesting challenges for clinical trials. The future could see the development of more compact devices with the help of diverse fields such as nanotechnology, microelectronics and advanced materials technology.